app.py

import streamlit as st
from einops import repeat
import numpy as np
import pandas as pd
import altair as alt

MAXDIP = 60.
XMAX = 30
YMAX = XMAX*np.tan(np.deg2rad(MAXDIP))

def fig_1(dip=26.6):
    '''
    AVO: Amplitude Versus Offset
    AVA: Amplitude Versus Angle
    compute AVA at the WB for a range of values,
    then plot using altair
    '''
    X = np.array([0,XMAX])
    dipping_reflector = np.array([0,np.abs(X[0]-X[1])*np.tan(np.deg2rad(dip))])

    df = pd.DataFrame({"x":X,
                       "z":dipping_reflector
                       }
                       )

    lines = alt.Chart(df).mark_line().encode(
        alt.X(field="x", type="quantitative", axis = alt.Axis(orient="top"), 
                                                              scale=alt.Scale(domain=[0,XMAX])),
        alt.Y(field="z", type="quantitative", scale=alt.Scale(domain=[0,YMAX],
                                                              reverse=True))
    ).properties(
        width=YMAX*10,
        height=XMAX*10
    )
    
    return lines

refector_dip = st.slider("Set reflector dip in degrees", min_value=0.1, max_value=MAXDIP, value=26.6)
# st.write("Poisson's ratio is:", p)


st.altair_chart(fig_1(refector_dip))